Brain tumor presenting as an acute pure motor hemiparesis

Acute pure motor hemiparesis is a clinical syndrome of isolated hemiparesis usually related to lacunar infarction, although other etiologies have been described. We recently encountered three patients with the abrupt onset of pure motor hemiparesis as the initial manifestation of primary or metastatic brain tumor. In each patient, early computed tomography demonstrated a nonhemorrhagic, right frontal, enhancing mass lesion. While the mechanism whereby brain tumor may present abruptly and simulate a stroke remains uncertain, these cases illustrate that pure motor hemiparesis can be the initial symptom of intracranial tumor. Early computed tomography or magnetic resonance imaging is suggested for all patients who present acutely with pure motor hemiparesis.     

Somatosensory evoked potentials in lacunar syndromes of pure motor and ataxic hemiparesis

Syndromes of hemiparetic lacunar infarction include pure motor hemiparesis and ataxic hemiparesis. Twelve such patients were evaluated with somatosensory evoked potentials. Potentials were delayed or absent in all 4 patients with ataxic hemiparesis and in 1 of 8 patients with pure motor hemiparesis. Unlike pure motor hemiparesis, ataxic hemiparesis appears to be associated with abnormal somatosensory evoked potentials. These abnormalities suggest that disturbance of afferent pathways are important in ataxic hemiparesis.     

Bilateral medial medullary infarction with oculomotor disorders.

BACKGROUND AND PURPOSE: We describe the first case of bilateral medial medullary infarction demonstrated by magnetic resonance imaging. We discuss the relation between this lesion and the oculomotor signs that were observed clinically. CASE DESCRIPTION: A 71-year-old man initially presented with pure motor hemiparesis, which progressed to complete quadriplegia. He also developed nearly complete vertical and horizontal ophthalmoplegia. Magnetic resonance imaging revealed upper medial medullary infarctions bilaterally that extended to the pontomedullary junction. CONCLUSIONS: We propose that the vertical oculomotor disorders resulted from involvement of the oculomotor system in the caudal brain stem, especially the caudal paramedian pontine reticular formations on both sides.     

Brain stem glioma in childhood: acute hemiplegic onset

Two children, age seven and 16 years, are described with the abrupt onset of a pure motor hemiplegia as the initial manifestation of a brain stem neoplasm. Subsequent rapid neurological deterioration localized the lesion to the brain stem and glioblastoma multiforme was diagnosed by surgical biopsy. It is suggested that brain stem gliomas with this unusual presentation are likely to be highly malignant and prone to rapid bulbar deterioration.     

Pure motor hemiparesis due to hypertensive putaminal haemorrhage

A hypertensive woman presenting as pure motor hemiparesis with rapid and complete recovery from the neurological deficit is described. The probable aetiology was primary hypertensive putaminal haemorrhage, as revealed by CT scan. This rare presentation has been described only once earlier and emphasizes the value of CT scanning as a tool for diagnosis of such cases.     

Neuropsychological abnormalities associated with lacunar infarction

The objective of this study was to assess neuropsychological abnormalities in 40 patients with lacunar infarction. Topography of infarction, presence of isolated or multiple silent infarcts and white matter hyperintensities were correlated with results of neuropsychological tests and subtypes of lacunar infarction. Patients were studied within 1 month after stroke. A total of 21 patients were males and the mean age was 70.7 years; 30% had a single infarction (mean number of infarctions was 3.4). Twelve patients had pure motor hemiparesis, 9 pure sensory stroke, 8 dysarthria-clumsy hand/ataxic hemiparesis, 8 atypical lacunar syndrome, and 3 sensorimotor stroke. The mean score of the Mini-Mental State Examination was 28.4. Mild cognitive impairment of subcortical vascular features occurred in 23 patients and isolated executive disturbances in 4. Neuropsychological results showed that patients with atypical lacunar syndrome followed by pure motor hemiparesis showed significantly more cognitive executive disturbances. Patients with dysarthria-clumsy hand/ataxic hemiparesis accounted for the best scores in some tests of visuoconstructive function and visual memory. In summary, mild neuropsychological disturbances (57.5%) are not infrequent in acute lacunar infarcts especially in patients with atypical lacunar syndrome and pure motor hemiparesis. Neuropsychological impairment should be considered as common clinical feature in acute lacunar infarction.     

Neurocysticercosis and pure motor hemiparesis

A 49-year-old man with meningeal cysticercosis presented with a pure motor hemiparesis. Computed tomography and magnetic resonance imaging showed a capsular infarction and a suprasellar cyst with surrounding arachnoiditis. Cerebrospinal fluid analysis confirmed the diagnosis as it showed positive immunologic reactions to cysticerci. This is the first reported case of pure motor hemiparesis due to a parasitic disease of the central nervous system.     

Ataxic hemiparesis: clinical, electrophysiologic, radiologic and pathologic observations

The present documentation of eight patients with the syndrome of ataxic hemiparesis consisted of one pathologically proven case of pontine glioma, one patient with brain stem metastasis from bronchogenic carcinoma revealed by computerized tomography and six patients with the clinical profile of ischemic stroke. Auditory brain stem responses were tested in five patients, which helped to localize the lesion to pons and medulla in the patient with brain stem metastasis, and rostral to midpons in three patients with the vascular syndrome. One patient with the classic clinical features of thalamic syndrome showed a normal response pattern. The pathogenesis of ataxic hemiparesis is discussed and sites of lesion other than pons which could account for the syndrome are suggested.     

Clinical-computed tomographic correlations of lacunar infarction in the Stroke Data Bank

Lacunar stroke was diagnosed in 337 (26%) of the 1,273 patients with cerebral infarction among the 1,805 total in the Stroke Data Bank. We analyzed the 316 patients with classic lacunar syndromes. Among these, 181 (57%) had pure motor hemiparesis, 63 (20%) sensorimotor syndrome, 33 (10%) ataxic hemiparesis, 21 (7%) pure sensory syndrome, and 18 (6%) dysarthria-clumsy hand syndrome. No striking differences were found among the risk factors for the lacunar subtypes, but differences were found between lacunar stroke as a group and other types of infarcts. Compared to 113 patients with large-vessel atherosclerotic infarction, those with lacunar stroke had fewer previous transient ischemic attacks and strokes. Compared to 246 with cardioembolic infarction, patients with lacunar stroke more frequently had hypertension and diabetes and less frequently had cardiac disease. We found a lesion in 35% of the lacunar stroke patients' computed tomograms, with most lesions located in the internal capsule and corona radiata. The mean infarct volume was greater in patients with pure motor hemiparesis or sensorimotor syndrome than in those with the other lacunar stroke subtypes. In patients with pure motor hemiparesis and infarcts in the posterior limb of the internal capsule, there was a correlation between lesion volume and hemiparesis severity except for the few whose infarct involved the lowest portion of the internal capsule; in these patients severe deficits occurred regardless of lesion volume. Taken together, the computed tomographic correlations with the syndromes of hemiparesis showed only slight support for the classical view of a homunculus in the internal capsule.     

Isolated Infarction of the Medullary Pyramid – A Rare Pure Motor Stroke

Acute pure motor hemiparesis can occur due to a vascular insult along the cortico spinal pathway. Rarely such a stroke can occur as a result of involvement of the pyramids located on the ventral aspect of the medulla. Neurological localization can be difficult in such strokes and moreover they can also pose imaging challenges since they are missed on the CT scans. So far only 4 such cases have been reported in literature. Here we present two cases of pure motor strokes caused by infarction of the medullary pyramids. We have described the anatomical correlates of the symptoms and signs and also highlight the importance of MRI in picking up these rare strokes.     

Progressive multifocal leukoencephalopathy in an adult patient with ICF syndrome

We report on a patient affected by ICF syndrome (immunodeficiency, centromeric instability of chromosomes 1, 9 and 16 and facial dysmorphism), who presented with slowing in mentation, mild right hemiparesis and focal motor seizures. MRI study of the brain suggested a diagnosis of progressive multifocal leukoencephalopathy (PML), which was confirmed by JC virus DNA detection on CSF by polymerase chain reaction (PCR). This is a unique case of adult infective neurological complication described in ICF Syndrome.     

Pathological yawning as a presenting symptom of brain stem ischaemia in two patients

Two cases of brain stem stroke involving the upper pons and the ponto-mesencephalic junction presented with transient excessive pathological yawning, associated with gait ataxia and in one subject with upper limb and facial hemiparesis. A causal relation is hypothesised between the brain stem lesion and pathological yawning, possibly related to denervation hypersensitivity of a putative brain stem yawn centre. Excessive yawning may herald brain stem ischaemia.     

Basilar artery stenosis mimicking the lacunar syndrome of pure motor hemiparesis

BACKGROUND: Stereotyped, repeated transient ischemic attacks manifesting as pure motor hemiparesis are most often attributed to ischemia of the internal capsule or ventral pons resulting from in situ disease of the small penetrating arteries. CASE DESCRIPTION: We report a 61-year-old man presenting with recurrent episodes of left-sided weakness consistent with the lacunar syndrome of pure motor hemiparesis. Subsequent neuroimaging revealed infarction of the right ventral pons and a critical basilar artery stenosis as the inciting lesion. Despite maximal antithrombotic therapy, he continued to have repeated symptoms. Angioplasty and stenting were attempted but both failed due to plaque recoil and technical difficulties. After the procedure, the patient had no further ischemic episodes and remained symptom-free at two months. CONCLUSIONS: This case illustrates the imprecise and discordant relationship between the mode of presentation of a stroke syndrome and its presumed pathophysiology. The lacunar syndrome of pure motor hemiparesis should be recognized by clinicians as a mode of stroke presentation due not only to small vessel disease, but also to large artery atherosclerotic disease such as basilar artery stenosis. Prompt institution of treatment can lead to a good clinical outcome.     

Discrete lesions in the sensorimotor control system. A clinical-topographical study of lacunar infarcts.

In 50 patients with computed tomography-verified small, deep, lacunar, infarcts from a prospective stroke registry, we studied the lesion site in relationship with the clinical syndromes pure motor stroke, sensorimotor stroke and ataxic hemiparesis. Seventy per cent (95% confidence interval: 57-83%) of the lesions were located in the posterior limb of the internal capsule or adjacent paraventricular region, affecting the corticospinal tract in pure motor stroke, as well as the thalamocortical tract in sensorimotor stroke, and the cerebellar (dentato(rubro)thalamocortical and corticopontocerebellar) pathways in ataxic hemiparesis. This most frequently involved area is supplied by the anterior choroidal artery, indicating that this artery is the predominant deep, penetrating artery involved in small vessel disease causing lacunar stroke syndromes.     

Successful surgical treatment of pontine vascular malformation in a 3-year old. Case report.

A 3-year-old male presented with progressive right hemiparesis. Clinical and radiological studies suggested the diagnosis of brain stem glioma. At surgery, a small vascular malformation of the pons was encountered. Although rare, vascular malformations must be considered in the differential diagnosis of brain stem masses.     

An unusual presentation of hypokalemic paralysis with evolving pure motor hemiparesis

Pure motor hemiparesis is a vascular syndrome that is occasionally mimicked by central or spinal pathologies. However, metabolic neuromuscular disorders have not been reported to mimic this condition. We present a 52-year-old male patient with hypokalemic paralysis who presented with the early symptoms of acute-onset pure motor hemiparesis. Neurological examinations revealed right-sided weakness without bulbar, extraocular, or respiratory involvement. Ischemic stroke was initially diagnosed on the basis of the acute-onset unilateral motor deficit and the patient’s history of hypertension, stroke, and previous cerebral infarctions. The right hemiparesis and weakness of the left limbs worsened on the day after admission. The patient’s weakness rapidly reversed after correction of hypokalemia, and a diagnosis of hypokalemic paralysis was finally established. This unusual hemineurological presentation should alert medical personnel to the possibility of reversible metabolic neuromuscular disorders, thereby avoiding delayed diagnosis.     

Pure motor stroke as the most frequent lacunar syndrome: A clinical update

Pure motor stroke (PMS), also known as pure motor hemiparesis, is the most common of any lacunar form (between one half and two thirds of cases, depending on the series). In an acute stroke registry, 733 patients presented a lacunar infarct and PMS accounted for 12.7% (n = 342) of all first-ever stroke patients and for 48% of all lacunar syndromes. The posterior limb of the internal capsule, corona radiata, and pons are the most frequent brain topographies. Infarcts in the mesencephalus or medullary pyramid have been exceptionally reported. This present update is focused on the clinical evidence and mechanisms underlying the relationship between PMS and different stroke etiologies.     

The role of ipsilateral primary motor cortex in movement control and recovery from brain damage

The role of ipsilateral motor areas for movement control is not yet fully understood. The relevance of these areas to the recovery of motor function following a brain lesion is a matter of dispute. It has recently been stated that increased ipsilateral activation following brain damage is maladaptive and hindering the process of recovery. Others have presented evidence that ipsilateral motor areas subserve motor recovery.A recent study published in Experimental Neurology [Lotze, M., Sauseng, P., Staudt, M., 2009. Functional relevance of ipsilateral motor activation in congenital hemiparesis as tested by fMRI-navigated TMS. Exp. Neurol., 217, 440-443.] on patients with congenital hemiparesis presents evidence for the importance of ipsilateral primary motor cortex and dorsal premotor cortex to movement control even in the absence of direct ipsilateral descending output in this special set of patients.This comment briefly summarizes the relevant findings supporting both views and discusses potential causes for the prima facie contradictory findings.     

Clinical study of 227 patients with lacunar infarcts

We describe an analysis of 227 patients with lacunar infarcts; 177 were inpatients and the remaining 50 were outpatients. The group comprised 11% of all inpatients with cerebrovascular pathology and 16% of all consecutive inpatients with brain infarcts studied at the Department of Neurology of the Hospital de la Santa Creu i Sant Pau. The main risk factors identified in these patients were arterial hypertension in 164 (72%), diabetes mellitus in 64 (28%), and heart disease in 58 (26%). The most common clinical syndromes were pure motor hemiparesis in 125 (55%), pure hemisensory stroke in 42 (18%), the sensorimotor deficit syndrome in 34 (15%), ataxic hemiparesis in seven (3%), and the dysarthria-clumsy hand syndrome in four (2%); atypical syndromes were observed in 15 patients (7%). Lacunes were demonstrated by computed tomography in 100 patients (44%) and by magnetic resonance imaging in 35 (78%) of the 45 patients in which it was applied. Magnetic resonance imaging was significantly better (p less than 0.001) than computed tomography for imaging lacunes, especially those located in either the pons (p less than 0.005) or the internal capsule (p less than 0.001). After the acute phase, mild or no neurologic disability was detected in 178 patients (78.4%), moderate disability persisted in 48 patients (21.1%), and severe disability was recorded in one case (0.4%). Lacunar infarcts are a clearly defined entity with characteristic clinical features and an excellent short-term prognosis. Magnetic resonance imaging is the current method of choice for demonstrating these small brain lesions.     

Lacunar syndromes due to brainstem infarct and haemorrhage.

Nine patients with brainstem infarct and two with brainstem haemorrhage presented with pure motor stroke, pure supranuclear facial palsy, sensorimotor stroke or ataxic hemiparesis. Despite the clinical similarity with hemispheric lacunes, brainstem infarcts causing lacunar syndromes probably have a greater tendency to progress. Small brainstem haemorrhages should also be considered as a cause of lacunar syndromes and the difficulty in differentiating them from small infarcts without CT is emphasised.